cappie/events.py

   1 #!/usr/bin/python
   2 ###############################################################################
   3 #                                                                             #
   4 # Cappie                                                                      #
   5 # Copyright (C) 2010 Michael Tremer                                           #
   6 #                                                                             #
   7 # This program is free software: you can redistribute it and/or modify        #
   8 # it under the terms of the GNU General Public License as published by        #
   9 # the Free Software Foundation, either version 3 of the License, or           #
  10 # (at your option) any later version.                                         #
  11 #                                                                             #
  12 # This program is distributed in the hope that it will be useful,             #
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of              #
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
  15 # GNU General Public License for more details.                                #
  16 #                                                                             #
  17 # You should have received a copy of the GNU General Public License           #
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
  19 #                                                                             #
  20 ###############################################################################
  21
  22 import os
  23 import subprocess
  24 import time
  25
  26 from errors import *
  27
  28 class Event(object):
  29         def __init__(self, interface):
  30                 self.cappie = interface.cappie
  31                 self.interface = interface
  32                 self.log = interface.log
  33                 self.db = self.cappie.db
  34
  35         def __str__(self):
  36                 return self.__class__.__name__
  37
  38         def addEvent(self, event):
  39                 return self.cappie.queue.add(event)
  40
  41         def run(self):
  42                 raise NotImplementedError
  43
  44
  45 class EventShell(Event):
  46         heartbeat = 0.1
  47         timeout = 10
  48
  49         def __init__(self, interface, script):
  50                 Event.__init__(self, interface)
  51
  52                 self.script = script
  53
  54         def run(self):
  55                 args = " ".join([self.script, self.interface.dev])
  56
  57                 start = time.time()
  58                 self.log.debug("Running: %s" % args)
  59
  60                 p = subprocess.Popen(args,
  61                         close_fds=True,
  62                         shell=True,
  63                         stdin=open("/dev/null", "r"),
  64                         stdout=subprocess.PIPE,
  65                         stderr=subprocess.STDOUT)
  66
  67                 while p.poll() is None:
  68                         time.sleep(self.heartbeat)
  69                         if (time.time() - start) > self.timeout:
  70                                 try:
  71                                         os.killpg(p.pid, 9)
  72                                 except OSError:
  73                                         pass
  74                                 raise EventTimeout, "Script took too long to return"
  75
  76                 for line in p.stdout.read().splitlines():
  77                         if not line: continue
  78                         self.log.debug("  %s" % line)
  79
  80                 self.cappie.log.debug("Child process returned with exit code: %s" % \
  81                         p.returncode)
  82
  83                 return p.returncode